ECE 4510/5530 Microcontroller Applications
Fall 2008
Homework Assignment #9
Total: 70 pts.
Due 3:30pm, Wednesday, November 19, 2008
You are to design the necessary glue logic and software for the interface problem as
follows. The peripheral device sends a 32-bit data PD31 – PD0 along with a validating
strobe signal STB# (active-low). The minimum pulse width for STB# is 2µs. The data
setup and hold time with respect to the asserted STB# is 25ns, respectively. The
minimum time period between STB# signals is not shorter than 30µs. The program
running on the microcontroller should take 16 32-bit data from this peripheral and store
them in a data array in memory. Only ports P and H, as well as external interrupt IRQ*
are available for this task. The CPU clock rate has been set to 8MHz.
a) Explain your design approach. That includes the mapping of the signals to
port
bits, the justification for using glue (external) logic and your algorithm to
this problem. (10 pts.)
b) Draw a detailed schematic diagram for the hardware part of this interface.
Your schematics should include Header connector and chip pin numbers,
respectively. All signal lines should be labeled. All port pins of the
9S12DP512 microcontoller that are used in your solution should be buffered.
(30 pts.)
c) Develop the software part of this interface in C. Choose the code, data, and
variable locations for your program such that it could run on the system in the
Lab but you are not required to prove that it has actually run. Turn in your C
source code along with the compiled .lst file and comment on your code for
full credit. (30 pts.)